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Lymph nodes, spleen, liver, lung and kidney obtained from pigs experimentally infected with two African Swine Fever Virus (ASFV) isolates of differing virulence were fixed by perfusion with glutaraldehyde and embedded in paraffin. An immunoperoxidase technique using a polyclonal anti-ASFV serum was performed on tissue sections in order to detect ASFV antigen. The distribution of ASFV antigen in such infected organs is shown and the differences between both infections compared and discussed. Monocytes, macrophages, hepatocytes, endothelial cells, neutrophils and epithelial cells were found to contain ASFV antigens.  相似文献   
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Cutaneous leiomyosarcomas are malignant mesenchymal tumors of smooth muscle origin and are reported occasionally in avian species. A 14-y-old male laboratory White Carneau pigeon (Columba livia) was presented for surgical excision of a cervical soft tissue mass. Ultrasonography with color flow Doppler imaging revealed multiple cavitations of mixed echogenicity within the mass and vascularization. Histologically, the dermis and subcutis were expanded by a densely cellular multinodular mass comprised of fusiform cells forming haphazardly arranged broad streams and short interwoven bundles, often surrounding blood vessels and variably sized cavitations. Neoplastic cells were strongly immunopositive for desmin and α–smooth muscle actin, and negative for pancytokeratin, S100, and von Willebrand factor. Based on histopathology and IHC findings, the cutaneous mass was diagnosed as leiomyosarcoma (LMS). The pigeon died 312 d post-operatively. Postmortem examination revealed masses infiltrating the left and right pulmonary airways and one hepatic nodule, but no regrowth at the surgical site. Histologic and IHC evaluation of the pulmonary and hepatic masses were consistent with LMS, representing metastatic foci from the primary cutaneous LMS. Our case highlights the malignant behavior and histomorphologic features of cutaneous LMS in an avian species.  相似文献   
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The Shuttleworth and Wallace model (SW) was evaluated to estimate latent heat flux above a drip-irrigated Cabernet Sauvignon vineyard, located in the Pencahue Valley, Region del Maule, Chile (35°22′ LS; 71°47′ LW; 150 m above sea level). The performance of the WS model (LEws) was evaluated against the eddy-covariance method (LEed) on a 30 min time interval. Results indicate that the root mean square error (RMSE) and mean absolute error (MAE) were 29 W m−2 and 22 W m−2, respectively. For the vine evapotranspiration (ETv), RMSE was 0.42 mm day−1 and MAE was 0.36 mm day−1. The largest disagreements between LEed and LEws were observed under dry atmospheric conditions. Also, the sensitivity analysis indicates that predicted ETv by the SW model was sensitive to errors of ±30% in leaf area index and mean stomatal resistance, but it was not affected by errors in the estimation of aerodynamic resistances.  相似文献   
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Routine histopathological diagnosis of one representative 3-month-old pig from a group suffering from diarrhoea revealed a massive degree of parasitation by Cryptosporidium parvum, with a concomitant infection by porcine circovirus type 2 (PCV2), that was confirmed by immunohistochemical procedures. The areas of intestine where parasites were more numerous presented abundant PCV2 infected cells in mucosa and submucosa. The concurrence of C. parvum, a rare primary intestinal pathogen in post-weaning and growing pigs, and PCV2 infections suggest an increased susceptibility as a result of an immunosuppression state.  相似文献   
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A total of 207 teeth belonging to 53 deer (Cervus elaphus hispanicus) from Sierra Morena (South of Spain) were analysed using histological thin sections and/or polished thick sections. Growth marks were observed in dentine and cementum of incisors, molars and canines. Tooth, region of the tooth, and type of preparation giving the best performance in terms of sharpness and interpretation ease of the growth marks, when used for Spanish deer ageing, were identified. The tissue chosen for the study was the cellular cementum of the inter-radicular pad from molars and the acellular cementum of the root from incisors, both observed through longitudinal cuts. Histological sections obtained with a conventional microtome were optimal for a reliable identification of the first growth marks. In sections thicker than 15 microm the first rest line, when observed in cementum can be confused with the cementum-dentine junction; whereas in the polished sections from molars it will not appear at all. Dentine interpretation was more difficult. Its observation should only be accomplished using cross-sections of the molar root. Secondary or accessory marks were visible in every tooth, being those from the molar pad the easiest to distinguish. Canines were the less suitable teeth for this study.  相似文献   
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Porcine Alv-Mphi from bronchoalveolar lavages were tested for their function in an in vitro foot-and-mouth disease virus (FMDV)-specific lymphoproliferative recall response. The Alv-Mphi were seen to be poor accessory cells when compared with peripheral blood monocytes. This poor capacity was evident despite an efficient expression of SLA-DR region antigens, and other co-stimulatory adhesion molecules. It was noted that Alv-Mphi secrete relatively little interleukin 1 (IL-1beta), with or without LPS induction, even though mRNA for the cytokine could be detected. In contrast, blood monocytes with their effective accessory activity were potent secretors of IL-1. Although this IL-1beta would be important with respect to the accessory capacity of monocytic cells, it was noted that the absence of bioactive IL-1 from the Alv-Mpi cultures was not solely responsible for their poor accessory function. In fact, the Alv-Mphi produced factors which not only inhibited IL-1 bioactivity, but were also responsible for a clear suppression of lymphoproliferation. This suppressor activity was dependent on the type of monocytic cell present in the culture, being more prominent when "scavenger" phagocytes were present. Thus, the major role of Alv-Mphi s not as an accessory cell akin to monocytes, but as both a scavenger cell, related to Mphi derived from monocytes in the absence of inflammatory signals, and an immunoregulatory cell.  相似文献   
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